Delegation is a usual management term that is used to indicate a style of leadership where the owner of the business or managers will delegate some of their powers (and responsibilities) to workers. It is not a free ride though as managers or owners need let go and trust their employees if they wish to be good at delegation.

I have also heard of a union delegate. The union delegate is a worker chosen by the workers and accepted by the union to as a leader charged with organizing the unionized workforce. However, there are times when I have heard that the union delegate has divided loyalties between the union and the management of the business. I have even heard cases where the managers have some how been able to get a union delegate that is totally loyal to them (but I hope this is a rare case as members paying union fees would not be happy with this situation).

You can look up a dictionary for the formal meanings, but management is a complex field involving organizing a business to produce stuff and make a profit and people are usually only part of that mix. I hope I have given you some direction to finding out more on this topic and a deeper understanding of the two terms.